(1) Field of the Invention
The present invention relates to a method for restoring compressor blade dovetails. More specifically, the present invention relates to a method of physically depositing parent metal onto a fretted or galled blade dovetail so as to restore the blade to operating condition.
(2) Description of Related Art
With reference to FIG. 1, there is illustrated a compressor disk and compressor blades assembly known to the art. Compressor disk 11 comprises a plurality of compressor disk dovetail slots 15 into which are inserted a plurality of compressor blades 13. The same assembly is used as well with fan disks and fan blades. With reference to FIG. 2, there is illustrated in greater detail the mating surfaces of the compressor blades 13, and the compressor disk 11. Fan and compressor blade 13 dovetail contact surfaces 19 are commonly subject to fretting, galling or wear in service due to contact with the mating surfaces 17 of fan and compressor disk dovetail slots 15. This damage frequently renders the blades 13 unsuitable for further service.
To inhibit such damage, lubricious anti-galling materials 21 are often applied to the dovetail contact surfaces 19. Such anti-galling materials 21 include, but are not limited to aluminum-bronze and copper-nickel or copper-nickel-indium materials. However, anti-galling materials 21 often suffer wear after extended use resulting in damage to the metallic structure of the blades 13. While it is common practice to reapply anti-galling materials 21 in such an event, there is little that can be done to replace or repair damage to the metallic structure of the blades 13. If sufficient damage has been done to the metallic structure of the blades 13, the blade must be disposed of in order to avoid system failure when in use.
What is therefore needed is a method of restoring blades 13 exhibiting damage resulting from fretting and galling to their original condition.